Bluebird skies, a few inches of fresh snow, and the whiff of diesel can only mean one thing on a recent morning at Keystone: cat skiing with Keystone Adventure Tours.

Sure you can skin your way to the top of Bergman, Erikson, or Independence Bowl but there are times when you don't mind siding with the industrial revolution. Hop in the cat and bet on anywhere from 6 to 10 laps, 25- to 45-degree pitches, and up to 1,000-foot descents through powder, glades, and pillows.